Catheter-based system having dongle with shape memory

ABSTRACT

A dongle couples an electrophysiologic catheter and a navigational system, including a patient interface unit (PIU). The dongle permits hardware normally carried on catheter control handle to be relocated onto the dongle to render catheter “greener” and less costly to manufacture use. The dongle having a support portion with flexibility, shape memory and/or varying degrees of stiffness also advantageously allows a user more control over the placement, position and orientation of the dongle. The dongle has a body with a first electrical interface unit, and a support portion with a second electrical interface unit, the support portion having an outer flexible tubular member with shape memory. In one embodiment, the support portion comprises a gooseneck tubing. In another embodiment, the support portion comprises a coiled spring.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of, and claims priority to and thebenefit of U.S. patent application Ser. No. 13/826,545 filed Mar. 14,2013, now U.S. Pat. No. 9,703,317, titled DONGLE WITH SHAPE MEMORY, theentire content of which is incorporated herein by reference.

FIELD OF INVENTION

The present invention relates to a dongle for coupling anelectrophysiologic catheter with a patient interface unit.

BACKGROUND OF INVENTION

Catheterization is used in diagnostic and therapeutic procedures. Forexample, a cardiac catheter is used for mapping and ablation in theheart to treat a variety of cardiac ailments, including cardiacarrhythmias, such as atrial flutter and atrial fibrillation whichpersist as common and dangerous medical ailments, especially in theaging population. Diagnosis and treatment of cardiac arrhythmias includemapping the electrical properties of heart tissue, especially theendocardium and the heart volume, and selectively ablating cardiactissue by application of energy. Such ablation can cease or modify thepropagation of unwanted electrical signals from one portion of the heartto another. The ablation process destroys the unwanted electricalpathways by formation of non-conducting lesions. Various energy deliverymodalities have been disclosed for forming lesions, and include use ofmicrowave, laser and more commonly, radiofrequency energies to createconduction blocks along the cardiac tissue wall. In a two-stepprocedure—mapping followed by ablation—electrical activity at pointswithin the heart is typically sensed and measured by advancing acatheter containing one or more electrical sensors (or electrodes) intothe heart, and acquiring data at a multiplicity of points. These dataare then utilized to select the endocardial target areas at whichablation is to be performed.

Electroanatomical navigation systems (ENS) are used in conjunction withcardiac diagnostic and therapeutic catheters. One such system is CARTOavailable from Biosense Webster of Irwindale, Calif., which is a 3-Dmapping system that provides electrophysiologists with magnetic locationtechnology and visualization data of catheter tip and curve location,anatomical mapping with rapid creation of high-resolution, CT-like maps,and a patient interface unit (PIU) as a central connection for cathetersand equipment.

Catheters for use with navigation systems have control handles whichcarry hardware, such as one or more printed circuit boards (PCB). Forexample, where electromagnetic sensor location data is transmitted via asensor cable extending through the catheter, one or more circuit boardshoused in the control handle may amplify the signals and convert them toa computer readable form before the data is transmitted to a signalprocessing unit of the navigation system. Although catheter handles arecostly, catheters are not easily sterilized so they are intended forsingle use only and are discarded along with their hardware/metalbearing handles.

Dongles are known. They are pieces of hardware that attach to a computeror other electronic device and enable additional functions. Donglestypically include at least one interface plug for connection to thecomputer or other electronic device to enable electrical connection withthe same. The dongle may include a flexible cable with a secondinterface plug.

With rising medical costs and the move toward moreenvironmentally-friendly (“greener”) catheters, current catheters aredesigned with the desire to relocate electronic hardware from thecontrol handles to elsewhere in the PIU or other components of thenavigation system. Some hardware may be relocated to a temporarylocation, such as a dongle, before finding a more permanent locationwithin the navigation system. In that regard, a free-hanging dongle or adongle with a flexible cable can be difficult to manage, especially asmore dongles are used to temporarily house more components. Afree-hanging dongle or one with a flexible cable may be prone to damageif knocked or bumped against other equipment and cause additionaltension on any extension cable between the dongle and the catheter.Moreover, a free-hanging dongle or one with a flexible cable may be anuisance to users who resort to using tape or zip-ties to secure orposition them.

Accordingly, there is a desire for a catheter dongle with a stiffeningmember that would enable a user to better position and secure thedongle. There is also a desire for a catheter dongle that is moredurable and less prone to damage from accidental bumping and addingstress or tension to catheter extension cables.

SUMMARY OF THE INVENTION

The present invention is directed to a dongle for coupling anelectrophysiologic catheter and a navigational system, including apatient interface unit (PIU). The dongle permits some of the hardwarenormally carried on the catheter control handle to be relocated so thatthe catheter—normally intended for single use—is less costly tomanufacture and contain less waste when discarded. The dongle having asupport portion with flexibility, shape memory and/or varying degrees ofstiffness also advantageously allows a user more control over theplacement, position and orientation of the dongle. The support portionprotects both the dongle body, as well as the catheter and the PIU byproviding elastic displacement for shock absorption where the dongle orthe catheter are accidentally bumped. The support portion also decreasesthe amount of stress and tension imposed on any extension cable that isconnecting the catheter to the dongle.

In one embodiment, the dongle has a body with a first electricalinterface unit, and a support portion with a second electrical interfaceunit, the support portion having an outer flexible tubular member withshape memory. In one embodiment, the support portion comprises agooseneck tubing. In another embodiment, the support portion comprises acoiled spring.

In a more detailed embodiment, the electrical interface unit maycomprises an electrical connection port or an electrical plug adapted totransmit electrical signals, where the electrical signals may compriseelectrical signals are representative of electrical activity in apatient's body, position data of a distal portion of the catheter withina patient's body, and/or RF energy.

In a more detailed embodiment, the body of the dongle houses componentsthat may be typically found in a catheter control handle, such aselectronic hardware, including printed circuit boards which may be usedto process electrical signals representative of position data of adistal portion of the catheter within a patient's body.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features and advantages of the present invention will bebetter understood by reference to the following detailed descriptionwhen considered in conjunction with the accompanying drawings wherein:

FIG. 1 is pictorial of a catheter-based electroanatomical navigationsystem using a dongle, in accordance with an embodiment of the presentinvention.

FIG. 2 is a schematic pictorial of the catheter-based electroanatomicalnavigation system of FIG. 1, in use in a cardiac procedure.

FIG. 3 is a side cross-sectional view of a catheter control handle, inaccordance with an embodiment of the present invention.

FIG. 4 is a side cross-sectional view of a dongle, in accordance with anembodiment of the present invention.

FIG. 5 is a side view of one embodiment of a flexible cable orgooseneck, shown partially broken away.

FIG. 5A is an enlarged detailed view of a portion of the flexible cableof FIG. 5.

FIG. 6 is a side cross-sectional view of another embodiment of aflexible cable or gooseneck.

FIG. 7 is a side view of a dongle in accordance with another embodimentof the present invention.

DETAILED DESCRIPTION OF THE INVENTION

With reference to FIG. 1, a catheter-based electroanatomical navigationsystem 10 is shown for use with a catheter 40, an extension cable 41 anda dongle 42, in accordance with the present invention. The system 10includes at least one monitor 12, a patient interface unit (PIU) 14, alocation pad 16, a signal processing unit 20, an ablation energygenerator 22, a workstation 24 and a printer 26. The monitor 12 displayspatient data and maps. The PIU 14 allows cable connections between thesignal processing unit 20 and all other system components. The locationpad 16 is for placement under a patient lying on a patient table 18,enabling accurate detection of catheter location. The signal processingunit 20 determines all location and performs ECG calculations. Thegenerator 22 may be an RF generator for supplying RF energy to thecatheter. The workstation 24 is a computer adapted for storing patientdata and maps. The printer 26 is provided to print color maps producedby the system 10. As shown in FIGS. 1 and 2, the dongle 42 extendsbetween PIU 14 and the catheter 40, providing an electrical connectionand performing any function(s) used or necessary for data gathered andtransmitted by the catheter to be understood and processed by the system10. Accordingly, the PIU 14 includes at least one electrical connectioninterface, for example, port 30 configured to interface with thecatheter 40 via the dongle 42.

In one embodiment, the catheter 40 has an elongated catheter body 112, adistal section 114 carrying tip and/or ring electrodes 117 and a controlhandle 116. As shown in FIG. 3, lead wires 140 are connected to theelectrodes 117 for receiving and transmitting electronic signals forgenerating patient data, including 3-D anatomical maps of the patient'sheart and ECG readings which are displayed on the monitor 14 and storedin the workstation 24. Moreover, electromagnetic position sensor(s)carried in the distal section 114 are responsive to external magneticfields generated by the location pad 16 below the patient table 18 forgenerating electrical signals representative of the location of thedistal tip section. Sensor cables 132 are connected from the positionsensors to transmit these signals. Both the lead wires 140 and thesensor cables 132 extend through the length of the catheter, passingthrough the distal tip section 114, the catheter body 112 and thecontrol handle 116. In that regard, a proximal end 116P of the controlhandle has at least one electrical connection port 30 to enableelectrical connection with the lead wires 140 and sensor cables 132.

In one embodiment, the extension cable 41 between the catheter 40 andthe dongle 42 has a proximal end 41P and a distal end 41D, as shown inFIG. 2. The distal end 41D is provided with a first interface, forexample, plug 43 configured to be received in the electrical connectionport 30 at the proximal end 116P of the control handle. The proximal end41P is provided with a second interface, for example, plug 44 configuredto be received in an electrical interface, for example, port 45 providedin a distal end of the dongle 42.

In one embodiment, the dongle 42 has a proximal support portionincluding a semi-rigid dongle cable 53, and an elongated distal body orhousing 54 with a proximal end 54P, a distal end 54D and a generallysealed interior cavity extending therebetween, as shown in FIG. 4. Atthe distal end 54D, the electrical port 45 is configured to receive thesecond interface plug 44 of the extension cable 41. At a proximal end ofthe cable 53, an electrical interface, for example, plug 55 isconfigured to be received in the electrical port 30 of the PIU 14.

In the illustrated embodiment of FIG. 4, the dongle 42 houses hardware,for example, at least one printed circuit board (PCB) 60 which receivesthe electrical signals representative of catheter location transmittedby the sensor cables 136 to through the extension cable. The PCB 60 mayamplify the signals and convert to a form readable by the signalprocessing unit 20 of the system 10 which are then transmitted via theproximal dongle cable 53.

With reference to FIGS. 5 and 6, the proximal cable 53 has an elongatedflexible outer tubing member 62 defining a lumen 63 through which donglewires 64 extend between the proximal and distal ends of the cable. Inaccordance with a feature of the present invention, the cable 53 issemi-rigid with shape memory so that the cable can be manipulated andconfigured by a user to selectively position or orient the dongle body54 as desired. In one embodiment, the outer tubing member 62 comprisesspirally wound flat strip(s) 67 of metal, metal alloy or generally rigidplastic material with longitudinal folds 69, interlocking adjacentlongitudinal side edges 71 to form what is commonly referred to as a“gooseneck” tubular structure with a corrugated-like profile whichprovides flexibility and shape memory such that it can be manipulatedinto and retain a variety of desired configurations. The tubularstructure may also act as a strain relief and/or a trunk cableinsulation covering. The wires 64 extending through the tubing member 62are protected and sealed within the tubing member 62.

FIG. 6 illustrates another embodiment of a flexible cable or goosenecktubular structure comprising an inner coiled spring 80 and an outersectional wire 82 wrapped around the coiled spring 80. In theillustrated embodiment, the underlying wire of the spring 80 has acircular cross-section and the outer sectional wire 82 has a triangularcross-section, wherein the underlying wire of the spring 80 is nestedbetween two inner vertices V of adjacent pairs of sectional wires 82.

In use, the dongle 42 is connected to the PIU 14 via the connector plug55 being received in the connector port 30, as shown in FIG. 2. A distalend of the dongle 42 receives the proximal connector 44 of the extensioncable 41. The distal connector 43 of the extension cable 41 is receivedin the connector port 30 of the control handle 116. In a diagnosticprocedure, as electrical signals are sensed by the tip and ringelectrodes 117 on the distal tip section 114 of the catheter 40positioned in patient's heart 125, the signals are transmitted via thelead wires 114 through the distal tip section 114, the catheter body 112and the control handle 116. The signals are transmitted from the controlhandle 116 to the PIU 14 for processing by the signal processing unit 20by the extension cable 41 and the dongle 42. In a therapeutic procedure,RF energy from the RF generator 22 of the system 10 is delivered to thetip and ring electrodes 117 via the PIU 14, the dongle 42, the extensioncable, and the lead wires 140 extending through the control handle 116,the catheter body 112 and the distal tip section 114.

For position sensing of the catheter distal tip section 114 in the heart125, electrical signals from the position sensors carried in thecatheter distal tip section are transmitted via the sensor cables 132which extends from the distal tip section, to the catheter body 12, andthe control handle 116. The signals are further transmitted via theextension cable 41 to the dongle 42 which provides the PCB 60 that mayamplify and/or convert the signals before transmitting them to the PIU14 for processing by the signal processing unit 20 of the system 20.

Accordingly, the dongle of the present invention renders a catheter moredisposable and “greener” by allowing expensive and metal-bearinghardware to be relocated from the catheter and onto the dongle.Moreover, the semi-rigid dongle of the present invention reduces therisk of damage to the dongle, the catheter and the navigation system byallowing the user more selection in the placement and positioning of thedongle.

In an alternate embodiment as shown in FIG. 7, a dongle 42′ isillustrated with a proximal support portion including a semi-rigiddongle arm 66 whose proximal end carries the electrical plug 55. The arm66 comprises a tightly coiled spring whose diameter may vary or beuniform throughout the length of the arm. The wires 64 extending throughthe spring are protected by the spring. The spring may be manufacturedwith different degrees of stiffness depending on the use andapplication, and be provided with a preformed shape. In the disclosedembodiment, the spring has sufficient stiffness to support the donglebody in a horizontal position but allows elastic bending or displacementwhere the dongle body is accidentally bumped.

It is understood by one of ordinary skill in the art that the body ofthe dongle may house a variety of electrical hardware for receiving andprocessing (including, for example, amplifying, converting, digitizing,etc.) a variety of electrical signals (including, for example, optical,audio, etc.) between the catheter and the navigation system, as neededor appropriate.

The preceding description has been presented with reference to presentlypreferred embodiments of the invention. Workers skilled in the art andtechnology to which this invention pertains will appreciate thatalterations and changes in the described structure may be practicedwithout meaningfully departing from the principal, spirit and scope ofthis invention. In that regard, the drawings are not necessarily toscale. Accordingly, the foregoing description should not be read aspertaining only to the precise structures described and illustrated inthe accompanying drawings, but rather should be read consistent with andas support to the following claims which are to have their fullest andfair scope.

What is claimed is:
 1. A system, comprising: a catheter comprising anelongated catheter body and a control handle at a proximal end of thecatheter body; a signal processing unit; and a dongle configured tocouple the control handle of the catheter to the signal processing unit,the dongle comprising: a dongle body having proximal and distal ends,the dongle body having a first electrical interface unit at its distalend configured for connection to a proximal end of the control handle;and a dongle support portion having proximal and distal ends andcomprising an outer flexible tubular member with shape memory, thedistal end of the dongle support portion being connected to the proximalend of the dongle body, the dongle support portion having a secondelectrical interface unit at its proximal end configured for connectionto the signal processing unit.
 2. The system of claim 1, wherein thedongle support portion comprises a gooseneck tubing.
 3. The system ofclaim 1, wherein the dongle support portion comprises a coiled spring.4. The system of claim 1, wherein the first electrical interface unitcomprises an electrical connection port configured to receive anelectrical plug.
 5. The system of claim 1, wherein the second electricalinterface unit comprises an electrical connection plug configured to bereceived in an electrical connection port.
 6. The system of claim 1,wherein the first electrical interface unit is configured to receiveelectrical signals from the catheter.
 7. The system of claim 6, whereinthe electrical signals are representative of electrical activity in apatient's body.
 8. The system of claim 6, wherein the electrical signalsare representative of position data of a distal portion of the catheterwithin a patient's body.
 9. The system of claim 1, wherein the firstelectrical interface unit is adapted to transmit RF energy to thecatheter.
 10. The system of claim 1, wherein the dongle body houses atleast one printed circuit board.
 11. The system of claim 10, wherein theat least one printed circuit board is configured to process electricalsignals representative of position data of a distal portion of thecatheter within a patient's body.
 12. The system of claim 1, wherein thecatheter further comprises a distal tip section carrying one or moreelectrodes and a lead wire for each of the one or more electrodes, eachof the lead wires being configured to transmit electrical signalsthrough the distal tip section, the catheter body and the controlhandle, and the control handle is configured to transmit the electricalsignals to the signal processing unit through the dongle.
 13. The systemof claim 1, further comprising an extension cable configured to connectthe dongle to the control handle of the catheter.
 14. The system ofclaim 13, wherein the catheter further comprises a distal tip sectioncarrying one or more electrodes and a lead wire for each of the one ormore electrodes, each of the lead wires being configured to transmitelectrical signals through the distal tip section, the catheter body andthe control handle, and the control handle is configured to transmit theelectrical signals to the signal processing unit through the extensioncable and the dongle.
 15. The system of claim 1, wherein the outerflexible tubular member of the dongle comprises at least one spirallywound flat strip.
 16. The system of claim 1, wherein the outer flexibletubular member of the dongle comprises an inner coiled spring and anouter sectional wire wrapped around the inner coiled spring.
 17. Thesystem of claim 16, wherein each segment of the outer sectional wirecomprises a triangular cross-section having an inner vertex, and whereineach segment of the inner coiled spring is nested between two innervertices of two adjacent segments of the outer sectional wire.
 18. Thesystem of claim 1, wherein the outer flexible tubular member comprises acoiled spring having an outer diameter that varies along a length of thesupport portion of the dongle.
 19. The system of claim 1, furthercomprising a patient interface unit configured to connect the dongle tothe signal processing unit.
 20. The system of claim 1, furthercomprising an ablation energy generator configured to supply ablationenergy to the catheter through the dongle and the control handle.